The invention concerns an assembly line of tires on their mounting wheels, with a view to obtaining mounted assemblies ready to be delivered at the right time to customers, generally motor vehicle manufacturers. It concerns, in particular, the means designed to use said assembly process and the product quality control means.
Such an assembly line contains, in the manner known through use, conveying means, such as conveyor belts or metal rollers making it possible to route the tires, wheels and mounted assemblies, respectively, from one point to another on the assembly line, said tires and said wheels coming from a supply warehouse by means of suitable pallets. The seats of each wheel rim, said wheel having been centered, as well as the beads of the tire are lubricated to facilitate, in known fashion, the mounting of the tire on the wheel rim, mounting being carried out by means of a mounting machine or mounter and the two beads of the tire being set in place by pressure with the aid of pressure arms and a roller. An inflation bell makes possible the introduction of gas for inflating the assembly by intervals between bead heels of the tire and the wheels.
Various documents describe machines for mounting or assembling tires on their rims. One example of such a machine is described in U.S. Pat. No. 2,661,053. A more advanced machine is described in U.S. Pat. No. 4,830,079 and consists of an apparatus for mounting tires on their rims without concern about the rim dimensions, whatever the diameter or overall width, the dimensions being detected before mounting.
The mounted assembly, inflated to the pressure recommended by the customer, is then conveyed to a machine for placement of the tire heels, which machine, by pressure on the sidewalls of said tire, makes possible a slight rotation of the beads and their repositioning under the effect of the inflation pressure. The mounted assembly, balanced on a balancing machine, is then conveyed on conveyor belts to a storage warehouse, where it will be picked up for delivery to the manufacturers.
The tires and wheels, on their arrival on the conveying means at the beginning of the assembly line, are not totally examined as to their dimensional conformity; only photoelectric cells signal their presence or absence.
The delivery of quality mounted assemblies to a manufacturer requires matching of the tire to the wheel to conform to the manufacturing customer""s demand, that is, it requires a good tire to be mounted on a good wheel. The mounted assembly will likewise be a quality product if it matches dimensionally what is requested and if it is inflated to the pressure recommended by the manufacturer.
In order to satisfy these requirements, the assembly line of mounted assemblies, according to the invention, comprising mainly of a machine for mounting the tire on the wheel, a device for inflating the mounted assembly and a machine for placement of tire bead heels as well as a balancing machine, is characterized in that it further comprises at least one means for checking the conformity of the diameter of the tire to be mounted and means for checking the conformity of the dimensions of the wheel.
One means of measuring the diameter of the tire. a diameter measured at the bead toe, can advantageously consist of photoelectric cell assemblies, placed on blocks above and below the tire laid flat and centered on a support. The disposition and number said cells makes possible the recognition of the diameter of the tire.
As for the means for checking the conformity of the mounting wheel, they advantageously make it possible to measure simultaneously the overall width of the wheel rim and the outline of the wheel disk, while checking at the same time the diameter of the rim, these three measurements being sufficient to characterize and recognize a wheel for a motor vehicle manufacturer. The means employed to make such measurements are advantageously combined in a single unit comprising mainly:
a centering system equipped with a cam-detector assembly and, more specifically, a centering system having a support arm of centering rollers on which a bent rod is fastened, the end of which is capable of moving into the slot of an arm that can be rotated on a fixed pin, said arm being equipped at its end with a metal plate or cam, arcuate in shape and of narrow width, said plate being capable, by rotation on the pin, of being positioned opposite one or more induction detectors integral with a frame, said system making it possible to check the conformity of the wheel diameter, and
an apparatus with two independent guide units. on which sensor-detector assemblies are mounted. said sensors being designed to be applied to one of the rim flanges and to the disk respectively and, more specifically, an apparatus composed of a first guide unit making possible, by means of a jack and guide rods, the vertical displacement of a support equipped on its edges with a sensor designed to be applied to one of the flanges of the rim, vertical displacement being measured by means of an ultrasonic detector, and a second guide unit independent of the first, but integral with the support and making possible, by means of a jack and guide rods, the vertical displacement of a support plate, on which is mounted a sensor designed to be applied to the disk of the wheel, a linear potentiometer making it possible to measure the displacement of the support.
It is advantageous for the assembly line to further include a means for detecting an unsuitably mounted assembly; said means can include of a device comprising a system of centering for the mounted assembly and a measuring system including a sensor, driven into one of the sidewalls of the tire with a constant force and combined with a detector capable of measuring said penetration depth.
The characteristics and advantages of the invention will be better understood by reference to the specification which follows and to the drawings unrestrictedly illustrating a working example of the invention: